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1.
Int J Mol Sci ; 23(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36012570

RESUMO

Tumor necrosis factor (TNF)-α is a pleiotropic cytokine implicated in the etiology of several autoimmune diseases, including rheumatoid arthritis (RA). TNF-α regulates diverse effector functions through the activation of TNF-α receptor (TNFR)1 and TNFR2. Although the detrimental role of this cytokine has been addressed in distinct disease settings, the effects of TNF-α on cytokine production by isolated CD4+ T helper type 1 (Th1) and Th17 cells, two T cell subpopulations that contribute to the pathogenesis of RA, have not been completely elucidated. Here, we show that TNF-α promotes a reduction and expansion in the frequency of both T cell subsets producing IFN-γ and IL-17, respectively. Selective blockade of TNFR1 or TNFR2 on Th1 and Th17 cells revealed that TNFR2 mediates the decrease in IFN-γ production, while signaling through both receptors augments IL-17 production. We also demonstrate that Th1, but not Th17 cells from RA patients present lower levels of TNFR1 compared to healthy controls, whereas TNFR2 expression on both T cell types is similar between patients and controls. Since TNF-α receptors levels in RA patients are not significantly changed by the therapeutic blockade of TNF-α, we propose that targeting TNFR2 may represent an alternative strategy to normalize the levels of key cytokines that contribute to RA pathogenesis.


Assuntos
Artrite Reumatoide , Receptores Tipo II do Fator de Necrose Tumoral , Receptores Tipo I de Fatores de Necrose Tumoral , Células Th1 , Células Th17 , Artrite Reumatoide/metabolismo , Citocinas/metabolismo , Humanos , Interleucina-17 , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
2.
Int J Mol Sci ; 23(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35805888

RESUMO

Damage-associated molecular patterns (DAMPs) play a critical role in dendritic cells (DCs) ability to trigger a specific and efficient adaptive immune response for different physiological and pathological scenarios. We have previously identified constitutive DAMPs (HMGB1 and Calreticulin) as well as new putative inducible DAMPs such as Haptoglobin (HP), from a therapeutically used heat shock-conditioned melanoma cell lysate (called TRIMEL). Remarkably, HP was shown to be the most abundant protein in the proteomic profile of heat shock-conditioned TRIMEL samples. However, its relative contribution to the observed DCs phenotype has not been fully elucidated. Human DCs were generated from monocytes isolated from PBMC of melanoma patients and healthy donors. DC lineage was induced with rhIL-4 and rhGM-CSF. After additional stimulation with HP, the proteome of these HP-stimulated cells was characterized. In addition, DCs were phenotypically characterized by flow cytometry for canonical maturation markers and cytokine production. Finally, in vitro transmigration capacity was assessed using Transwell plates. Our results showed that the stimulation with HP was associated with the presence of exclusive and higher relative abundance of specific immune-; energy production-; lipid biosynthesis-; and DAMPs-related proteins. Importantly, HP stimulation enhanced the expression of specific DC maturation markers and pro-inflammatory and Th1-associated cytokines, and an in vitro transmigration of primary human DCs. Taken together, these data suggest that HP can be considered as a new inducible DAMP with an important role in in vitro DC activation for cancer immunotherapy.


Assuntos
Melanoma , Monócitos , Diferenciação Celular , Citocinas/metabolismo , Células Dendríticas , Haptoglobinas/metabolismo , Humanos , Leucócitos Mononucleares/metabolismo , Melanoma/metabolismo , Monócitos/metabolismo , Fenótipo , Proteômica
3.
Rev Chilena Infectol ; 35(4): 455-457, 2018 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-30534936

RESUMO

In Chile, there are few studies about seroprevalence of IgG antibodies against hepatitis E virus (HEV) in blood banks, between 4 and 8%. The development of new techniques with greater sensitivity and specificity, account for an increase in the seroprevalence of HEV in various countries, the current status in Chile being unknown. In the present study, we determined the seroprevalence of anti-HEV IgG in blood donors of the Clinical Hospital University of Chile, with last generation ELISA techniques. Out of a total of 186 samples, collected in 2014, 56 (30.1%) were positive, without gender differences, but with a significant increase with age (p < 0.001). These results show an increase in the seroprevalence of HEV in blood donors performed with immunoassays of greater sensitivity.


Assuntos
Doadores de Sangue , Anticorpos Anti-Hepatite/sangue , Hepatite E/epidemiologia , Adolescente , Adulto , Idoso , Chile/epidemiologia , Feminino , Hepatite E/diagnóstico , Vírus da Hepatite E/imunologia , Hospitais Universitários , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Adulto Jovem
4.
Rev. chil. infectol ; 35(4): 455-457, ago. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-1042650

RESUMO

Resumen En Chile, existen escasos estudios de seroprevalencia de anticuerpos IgG anti virus hepatitis E (VHE) en bancos de sangre, entre 4 y 8%. El desarrollo de nuevas técnicas con mayor sensibilidad y especificidad, dan cuenta de un aumento de la seroprevalencia de VHE en diversos países, siendo desconocido el estado actual en Chile. En el presente estudio, determinamos la seroprevalencia de IgG anti VHE en donantes de sangre del Hospital Clínico Universidad de Chile, con técnicas de ELISA de última generación. De un total de 186 muestras, recolectadas el año 2014, 56 (30,1%) resultaron positivas, sin diferencias de género, pero con un incremento significativo con la edad (p < 0,001). Estos resultados muestran un aumento en la seroprevalencia de VHE en donantes de sangre realizados con inmunoensayos de mayor sensibilidad.


In Chile, there are few studies about seroprevalence of IgG antibodies against hepatitis E virus (HEV) in blood banks, between 4 and 8%. The development of new techniques with greater sensitivity and specificity, account for an increase in the seroprevalence of HEV in various countries, the current status in Chile being unknown. In the present study, we determined the seroprevalence of anti-HEV IgG in blood donors of the Clinical Hospital University of Chile, with last generation ELISA techniques. Out of a total of 186 samples, collected in 2014, 56 (30.1%) were positive, without gender differences, but with a significant increase with age (p < 0.001). These results show an increase in the seroprevalence of HEV in blood donors performed with immunoassays of greater sensitivity.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Doadores de Sangue , Anticorpos Anti-Hepatite/sangue , Hepatite E/epidemiologia , Imunoglobulina G/sangue , Estudos Soroepidemiológicos , Chile/epidemiologia , Prevalência , Sensibilidade e Especificidade , Vírus da Hepatite E/imunologia , Hepatite E/diagnóstico , Hospitais Universitários
5.
Front Immunol ; 8: 1350, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29109727

RESUMO

There is growing interest in the use of tolerogenic dendritic cells (tolDCs) as a potential target for immunotherapy. However, the molecular bases that drive the differentiation of monocyte-derived DCs (moDCs) toward a tolerogenic state are still poorly understood. Here, we studied the transcriptional profile of moDCs from healthy subjects, modulated with dexamethasone (Dex) and activated with monophosphoryl lipid A (MPLA), referred to as Dex-modulated and MPLA-activated DCs (DM-DCs), as an approach to identify molecular regulators and pathways associated with the induction of tolerogenic properties in tolDCs. We found that DM-DCs exhibit a distinctive transcriptional profile compared to untreated (DCs) and MPLA-matured DCs. Differentially expressed genes downregulated by DM included MMP12, CD1c, IL-1B, and FCER1A involved in DC maturation/inflammation and genes upregulated by DM included JAG1, MERTK, IL-10, and IDO1 involved in tolerance. Genes related to chemotactic responses, cell-to-cell signaling and interaction, fatty acid oxidation, metal homeostasis, and free radical scavenging were strongly enriched, predicting the activation of alternative metabolic processes than those driven by counterpart DCs. Furthermore, we identified a set of genes that were regulated exclusively by the combined action of Dex and MPLA, which are mainly involved in the control of zinc homeostasis and reactive oxygen species production. These data further support the important role of metabolic processes on the control of the DC-driven regulatory immune response. Thus, Dex and MPLA treatments modify gene expression in moDCs by inducing a particular transcriptional profile characterized by the activation of tolerance-associated genes and suppression of the expression of inflammatory genes, conferring the potential to exert regulatory functions and immune response modulation.

6.
Front Immunol ; 7: 458, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27826300

RESUMO

Tolerogenic dendritic cells (TolDCs) are promising tools for therapy of autoimmune diseases, such as rheumatoid arthritis (RA). Here, we characterize monocyte-derived TolDCs from RA patients modulated with dexamethasone and activated with monophosphoryl lipid A (MPLA), referred to as MPLA-tDCs, in terms of gene expression, phenotype, cytokine profile, migratory properties, and T cell-stimulatory capacity in order to explore their suitability for cellular therapy. MPLA-tDCs derived from RA patients displayed an anti-inflammatory profile with reduced expression of co-stimulatory molecules and high IL-10/IL-12 ratio, but were capable of migrating toward the lymphoid chemokines CXCL12 and CCL19. These MPLA-tDCs induced hyporesponsiveness of autologous CD4+ T cells specific for synovial antigens in vitro. Global transcriptome analysis confirmed a unique transcriptional profile of MPLA-tDCs and revealed that RA-associated genes, which were upregulated in untreated DCs from RA patients, returned to expression levels of healthy donor-derived DCs after treatment with dexamethasone and MPLA. Thus, monocyte-derived DCs from RA patients have the capacity to develop tolerogenic features at transcriptional as well as at translational level, when modulated with dexamethasone and MPLA, overcoming disease-related effects. Furthermore, the ability of MPLA-tDCs to impair T cell responses to synovial antigens validates their potential as cellular treatment for RA.

7.
J Oral Pathol Med ; 45(2): 127-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26102283

RESUMO

OBJECTIVE: Graft-versus-host disease (GVHD) is one of the main complications after haematopoietic stem cell transplantation. Clinical features of GVHD include either an acute (aGVHD) or a chronic (cGVHD) condition that affects locations such as the oral mucosa. While the involvement of the host's dendritic cells (DCs) has been demonstrated in aGVHD, the origin (donor/host) and mechanisms underlying oral cGVHD have not been completely elucidated. In this study, we intend to determine the origin of DCs present in mucosal tissue biopsies from the oral cavity of transplanted patients affected by cGVHD. METHODS: We purified DCs, from oral biopsies of three patients with cGVHD, through immunobeads and subsequently performed DNA extraction. The origin of the obtained DCs was determined by PCR amplification of 13 informative short tandem repeat (STR) alleles. We also characterised the DCs phenotype and the inflammatory infiltrate from biopsies of two patients by immunohistochemistry. RESULTS: Clinical and histological features of the biopsies were concordant with oral cGVHD. We identified CD11c-, CD207- and CD1a-positive cells in the epithelium and beneath the basal layer. Purification of DCs from the mucosa of patients affected by post-transplantation cGVHD was >95%. PCR-STR data analysis of DCs DNA showed that 100% of analysed cells were of donor origin in all of the evaluated patients. CONCLUSION: Our results demonstrate that resident DCs isolated from the oral tissue of allotransplanted patients affected by cGVHD are originated from the donor. Further research will clarify the role of DCs in the development and/or severity of oral cGVHD.


Assuntos
Células Dendríticas/patologia , Doença Enxerto-Hospedeiro/patologia , Transplante de Células-Tronco Hematopoéticas/métodos , Doenças da Boca/etiologia , Doenças da Boca/patologia , Mucosa Bucal/patologia , Quimeras de Transplante , Adolescente , Adulto , Antígenos CD/análise , Antígenos CD1/análise , Antígeno CD11c/análise , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Lectinas Tipo C/análise , Masculino , Lectinas de Ligação a Manose/análise , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Boca , Transplante Homólogo , Adulto Jovem
8.
PLoS One ; 9(1): e85930, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24465795

RESUMO

Natural rubber latex (NRL; Hevea brasiliensis) allergy is an IgE-mediated reaction to latex proteins. When latex glove exposure is the main sensitizing agent, Hev b 5 is one of the major allergens. Dendritic cells (DC), the main antigen presenting cells, modulated with pharmacological agents can restore tolerance in several experimental models, including allergy. In the current study, we aimed to generate DC with tolerogenic properties from NRL-allergic patients and evaluate their ability to modulate allergen-specific T and B cell responses. Here we show that dexamethasone-treated DC (dxDC) differentiated into a subset of DC, characterized by low expression of MHC class II, CD40, CD80, CD86 and CD83 molecules. Compared with LPS-matured DC, dxDC secreted lower IL-12 and higher IL-10 after CD40L activation, and induced lower alloantigenic T cell proliferation. We also show that dxDC pulsed with the dominant Hev b 5 T-cell epitope peptide, Hev b 5(46-65), inhibited both proliferation of Hev b 5-specific T-cell lines and the production of Hev b 5-specific IgE. Additionally, dxDC induced a subpopulation of IL-10-producing regulatory T cells that suppressed proliferation of Hev b 5-primed T cells. In conclusion, dxDC generated from NRL-allergic patients can modulate allergen-specific T-cell responses and IgE production, supporting their potential use in allergen-specific immunotherapy.


Assuntos
Alérgenos/imunologia , Células Dendríticas/imunologia , Imunoglobulina E/imunologia , Hipersensibilidade ao Látex/imunologia , Linfócitos T/imunologia , Adulto , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos de Plantas/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Linhagem Celular , Proliferação de Células , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Dexametasona/farmacologia , Epitopos de Linfócito T/imunologia , Feminino , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Interleucina-10/imunologia , Interleucina-10/metabolismo , Masculino , Pessoa de Meia-Idade , Peptídeos/imunologia , Proteínas de Plantas/imunologia , Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Adulto Jovem
9.
J Transl Med ; 11: 128, 2013 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-23706017

RESUMO

BACKGROUND: Generation of tolerogenic dendritic cells (TolDCs) for therapy is challenging due to its implications for the design of protocols suitable for clinical applications, which means not only using safe products, but also working at defining specific biomarkers for TolDCs identification, developing shorter DCs differentiation methods and obtaining TolDCs with a stable phenotype. We describe here, a short-term protocol for TolDCs generation, which are characterized in terms of phenotypic markers, cytokines secretion profile, CD4+ T cell-stimulatory ability and migratory capacity. METHODS: TolDCs from healthy donors were generated by modulation with dexamethasone plus monophosphoryl lipid A (MPLA-tDCs). We performed an analysis of MPLA-tDCs in terms of yield, viability, morphology, phenotypic markers, cytokines secretion profile, stability, allogeneic and antigen-specific CD4+ T-cell stimulatory ability and migration capacity. RESULTS: After a 5-day culture, MPLA-tDCs displayed reduced expression of costimulatory and maturation molecules together to an anti-inflammatory cytokines secretion profile, being able to maintain these tolerogenic features even after the engagement of CD40 by its cognate ligand. In addition, MPLA-tDCs exhibited reduced capabilities to stimulate allogeneic and antigen-specific CD4+ T cell proliferation, and induced an anti-inflammatory cytokine secretion pattern. Among potential tolerogenic markers studied, only TLR-2 was highly expressed in MPLA-tDCs when compared to mature and immature DCs. Remarkable, like mature DCs, MPLA-tDCs displayed a high CCR7 and CXCR4 expression, both chemokine receptors involved in migration to secondary lymphoid organs, and even more, in an in vitro assay they exhibited a high migration response towards CCL19 and CXCL12. CONCLUSION: We describe a short-term protocol for TolDC generation, which confers them a stable phenotype and migratory capacity to lymphoid chemokines, essential features for TolDCs to be used as therapeutics for autoimmunity and prevention of graft rejection.


Assuntos
Movimento Celular , Quimiocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Dexametasona/farmacologia , Lipídeo A/análogos & derivados , Autoimunidade , Biomarcadores/metabolismo , Linfócitos T CD4-Positivos/citologia , Diferenciação Celular , Citocinas/metabolismo , Células Dendríticas/citologia , Citometria de Fluxo , Humanos , Lipídeo A/farmacologia , Fenótipo , Receptores CCR7/metabolismo , Receptores CXCR4/metabolismo
10.
Cancer Immunol Immunother ; 62(4): 761-72, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23242374

RESUMO

INTRODUCTION: Immunization with autologous dendritic cells (DCs) loaded with a heat shock-conditioned allogeneic melanoma cell lysate caused lysate-specific delayed type hypersensitivity (DTH) reactions in a number of patients. These responses correlated with a threefold prolonged long-term survival of DTH(+) with respect to DTH(-) unresponsive patients. Herein, we investigated whether the immunological reactions associated with prolonged survival were related to dissimilar cellular and cytokine responses in blood. MATERIALS AND METHODS: Healthy donors and melanoma patient's lymphocytes obtained from blood before and after vaccinations and from DTH biopsies were analyzed for T cell population distribution and cytokine release. RESULTS/DISCUSSION: Peripheral blood lymphocytes from melanoma patients have an increased proportion of Th3 (CD4(+) TGF-ß(+)) regulatory T lymphocytes compared with healthy donors. Notably, DTH(+) patients showed a threefold reduction of Th3 cells compared with DTH(-) patients after DCs vaccine treatment. Furthermore, DCs vaccination resulted in a threefold augment of the proportion of IFN-γ releasing Th1 cells and in a twofold increase of the IL-17-producing Th17 population in DTH(+) with respect to DTH(-) patients. Increased Th1 and Th17 cell populations in both blood and DTH-derived tissues suggest that these profiles may be related to a more effective anti-melanoma response. CONCLUSIONS: Our results indicate that increased proinflammatory cytokine profiles are related to detectable immunological responses in vivo (DTH) and to prolonged patient survival. Our study contributes to the understanding of immunological responses produced by DCs vaccines and to the identification of follow-up markers for patient outcome that may allow a closer individual monitoring of patients.


Assuntos
Vacinas Anticâncer/administração & dosagem , Citocinas/imunologia , Células Dendríticas/imunologia , Imunoterapia Adotiva/métodos , Melanoma/terapia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Vacinas Anticâncer/imunologia , Feminino , Humanos , Hipersensibilidade Tardia/imunologia , Masculino , Melanoma/sangue , Melanoma/imunologia , Pessoa de Meia-Idade , Células Th1/imunologia , Células Th17/imunologia , Adulto Jovem
11.
Rheumatol Int ; 32(6): 1819-25, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21769486

RESUMO

Citrullinated vimentin (cVIM) is one of the antigens specifically targeted by anti-citrullinated protein antibodies (ACPA) in rheumatoid arthritis (RA) patients. The association between ACPA and certain HLA-DRB1 alleles, those coding for the shared epitope (SE), suggests that this response could be T-cell mediated. HLA-DR9 alleles, which do not code for the SE, have recently been associated with ACPA (+) RA. The objective of this work was to study CD4+ T cell responses to cVIM in RA patients and healthy controls carrying HLA-DR9 alleles. Fourteen RA patients and ten healthy controls previously genotyped for HLA-DRB1 were studied for the presence of serum anti-cVIM antibodies by Western blot and ELISA. Peripheral blood mononuclear cells were stimulated with native vimentin and cVIM, and CD4+ T cells proliferation was assessed by flow cytometry. Citrulline-specific CD4+ T cells proliferation was found not only in RA patients but also in healthy controls. Although most patients carrying HLA-DR9 alleles present anti-cVIM antibodies, HLA-DR9 alleles were associated with weaker cVIM-driven CD4+ T-cell responses among RA patients. These results suggest that HLA-DR9 alleles could exert a protective effect on the recognition of cVIM epitopes by CD4+ T cells. In this context, other citrullinated proteins may break T and B cell tolerance, with cVIM only acting as a cross-reactive target for ACPA.


Assuntos
Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Linfócitos T CD4-Positivos/imunologia , Citrulina/imunologia , Subtipos Sorológicos de HLA-DR/genética , Vimentina/imunologia , Adulto , Idoso , Autoanticorpos/sangue , Western Blotting , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Chile , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Genótipo , Humanos , Epitopos Imunodominantes , Ativação Linfocitária , Pessoa de Meia-Idade , Fenótipo
12.
J Clin Oncol ; 27(6): 945-52, 2009 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-19139436

RESUMO

PURPOSE: The aim of this work was to assess immunologic response, disease progression, and post-treatment survival of melanoma patients vaccinated with autologous dendritic cells (DCs) pulsed with a novel allogeneic cell lysate (TRIMEL) derived from three melanoma cell lines. PATIENTS AND METHODS: Forty-three stage IV and seven stage III patients were vaccinated four times with TRIMEL/DC vaccine. Specific delayed type IV hypersensitivity (DTH) reaction, ex vivo cytokine production, and regulatory T-cell populations were determined. Overall survival and disease progression rates were analyzed using Kaplan-Meier curves and compared with historical records. RESULTS: The overall survival for stage IV patients was 15 months. More than 60% of patients showed DTH-positive reaction against the TRIMEL. Stage IV/DTH-positive patients displayed a median survival of 33 months compared with 11 months observed for DTH-negative patients (P = .0014). All stage III treated patients were DTH positive and remained alive and tumor free for a median follow-up period of 48 months (range, 33 to 64 months). DTH-positive patients showed a marked reduction in the proportion of CD4+ transforming growth factor (TGF) beta+ regulatory T cells compared to DTH-negative patients (1.54% v 5.78%; P < .0001). CONCLUSION: Our findings strongly suggest that TRIMEL-pulsed DCs provide a standardized and widely applicable source of melanoma antigens, very effective in evoking antimelanoma immune response. To our knowledge, this is the first report describing a correlation between vaccine-induced reduction of CD4+TGFbeta+ regulatory T cells and in vivo antimelanoma immune response associated to improved patient survival and disease stability.


Assuntos
Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Melanoma/imunologia , Neoplasias Cutâneas/imunologia , Adulto , Progressão da Doença , Feminino , Seguimentos , Humanos , Hipersensibilidade Tardia/imunologia , Masculino , Melanoma/mortalidade , Melanoma/terapia , Pessoa de Meia-Idade , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/terapia , Análise de Sobrevida , Linfócitos T Reguladores/imunologia , Fator de Crescimento Transformador beta/biossíntese
13.
Rev Med Chil ; 133(8): 887-93, 2005 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-16163426

RESUMO

BACKGROUND: Multiple myeloma is rarely curable. Advances in high dose chemotherapy and stem cell transplantation have improved overall survival and event-free disease periods, but relapses are inevitable. AIM: To report our experience with AT in multiple myeloma, between 1994 and 2003. MATERIAL AND METHODS: Retrospective analysis of 20 patients (12 women), with a mean age of 51.1 years. VAD (vincristine, doxorubicin and dexamethasone) was used as initial therapy in 19 patients. High dose cyclophosphamide (11 patients) and variations of VAD regimen (7) associated with granulocyte colony stimulating factor were used for peripheral-blood stem cell harvest. The conditioning regimen consisted of melphalan 200 mg/m2 followed by the reinfusion of peripheral-blood stem cells 24 hours later. The median number of CD34 cells infused was 3.3x10(6)/kg. Three patients were subjected to a second auto graft and one to a non-myeloablative transplant. Mean follow up was 35.5 months. RESULTS: Mucositis and febrile neutropenia were common complications. The median number of days for neutrophil engraftment was 9 (range 8-11) and for platelets, 10 (range 7-13). No patient died. Complete remission was obtained in 60% (12/20), progression-free survival was 30 months and overall median survival, 47 months. CONCLUSIONS: The AT with high-dose melphalan is a safe procedure in our hospital, without mortality and engraftment in all the patients. Complete remission and progression free survival were similar to those reported abroad but the overall median survival was lower.


Assuntos
Mieloma Múltiplo/terapia , Transplante de Células-Tronco de Sangue Periférico , Condicionamento Pré-Transplante , Adulto , Antineoplásicos/uso terapêutico , Terapia Combinada , Intervalo Livre de Doença , Feminino , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Autólogo , Resultado do Tratamento
14.
Mol Diagn ; 9(1): 35-40, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16035733

RESUMO

OBJECTIVE: In order to evaluate the stability of Trypanosoma cruzi kinetoplast DNA (kDNA), the blood samples from seven patients with Chagas disease were stored in different buffers and at different temperatures. METHODS: Three different buffers were used: buffer A, 6 mol/L guanidine-HCl; buffer B, 6M guanidine-HCl and 0.2M EDTA pH 7.5; and buffer C, 6M guanidine-HCl, 0.2M EDTA pH 7.5 and 10 microM dl-alpha-tocopherol (Roche, Basal, Switzerland). Two temperatures were used: 4 degrees C and 25 degrees C. Vitamin E was added to the blood lysates as an antioxidant. T. cruzi kDNA was obtained by phenol extraction, and then PCR amplifications and Southern blot were carried out in each DNA sample up to 90 days of blood storage. The iron content of each sample was determined by atomic absorption spectrophotometry. RESULTS: Overall, there is an association between T. cruzi kDNA stability and the storage time of blood samples. No significant differences were detected in T. cruzi kDNA stability in the presence or absence of vitamin E or with citrate or EDTA as an anticoagulant. There was no statistical difference in the failure of PCR-based kDNA detection with these different storage buffers, temperatures or iron levels. CONCLUSIONS: The blood lysates promote T. cruzi kDNA damage in a time-dependent manner that reduces the ability to detect the genomic DNA of an infectious agent by PCR. The high concentration of guanidine-HCl denatured proteins in these storage conditions probably denotes a non-enzymatic kDNA lysis.


Assuntos
Doença de Chagas/diagnóstico , DNA de Cinetoplasto/sangue , Reação em Cadeia da Polimerase , Manejo de Espécimes/métodos , Trypanosoma cruzi/isolamento & purificação , Animais , Anticoagulantes/química , Soluções Tampão , DNA de Cinetoplasto/química , Ácido Edético/química , Humanos , Sensibilidade e Especificidade , Trypanosoma cruzi/genética , Vitamina E/química
15.
Rev Med Chil ; 132(9): 1115-26, 2004 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-15543770

RESUMO

An alternative strategy for cancer treatment is the manipulation of the immune system, denominated cancer immunotherapy. The immunotherapeutical use of cells of the immune system, like dendritic cells (DC), is being explored in different clinical protocols. Recently, we finalized a clinical phase I protocol, for the treatment of malignant melanoma, using DCs loaded with tumor lysates. Our results indicate that the subcutaneous application of DCs do not produce adverse effects. We also observed an increase of tumor specific T lymphocytes precursors in the blood, associated to hypersensitivity reactions (DTH) in 60% of the treated patients. In most cases, an stability in the disease was observed, although without a significant association between vaccination and survival. Additionally, therapies based on Interleukin-2 (IL-2) have been used with relative success in the treatment of some kind of tumors since 1985. However, problems associated to the toxicity of IL-2 still restrict its massive use. Our direct experience with the use of IL-2, indicates that low doses and its subcutaneous application, maintains the beneficial effects for patients, eliminating the adverse effects. Based on the accumulated evidence during last the five years, we decided to implement an optimized clinical protocol, which alternatively combines dendritic cells vaccines with the use of low doses of IL-2 for the reinforcement of the immunological system.


Assuntos
Vacinas Anticâncer/uso terapêutico , Células Dendríticas/imunologia , Imunoterapia , Interleucina-2/imunologia , Melanoma/terapia , Neoplasias Cutâneas/terapia , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Células Dendríticas/transplante , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Hipersensibilidade Tardia , Imunoterapia/efeitos adversos , Interleucina-2/efeitos adversos , Interleucina-2/uso terapêutico , Melanoma/imunologia , Pulsoterapia , Neoplasias Cutâneas/imunologia , Linfócitos T Citotóxicos/imunologia
16.
J Med Virol ; 72(4): 661-7, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14981770

RESUMO

Human herpesvirus-8 (HHV-8) causes Kaposi's sarcoma (KS) and lymphoproliferative disorders in both HIV-infected and uninfected patients. HHV-8 has a worldwide occurrence but infection rates vary according to a combination of geographic and behavioral risks. The main transmission route seems to be sexual, nevertheless, nasal secretions, saliva, blood, and organ graft have been proposed. HHV-8 was postulated as a new infectious agent for screening in blood donors. The aim of this study was to evaluate the prevalence of antibodies against HHV-8 antigens in blood donors of South America. Serum samples from 2,470 blood donors from Argentina, Brazil, and Chile corresponding to five geographic regions were studied by indirect immunofluorescence assay (IFA). Seroprevalence rate was 3.7% (92/2,470; 95% CI 2.9-4.5) in the entire blood donor population distributed as follows: Argentina, 4.0% (Buenos Aires city, 4.3%; Bahia Blanca, 2.4%; and Córdoba, 4.0%), Campinas (Brazil), 2.8%; and Santiago de Chile, 3.0%. There was no difference (P>0.05) between men and women or age related, except in Brazil where positive cases were 30-49-year-old males. The present study, which includes different geographical areas of multiple countries from South America, has not been done before. The results show similar prevalence rates among the studied zones corresponding to low-prevalence regions. South America is a large sub-continent with a wide spectrum of population and geographical characteristics, thus, more HHV-8 prevalence studies should be necessary to establish possible regional differences.


Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue , Infecções por Herpesviridae/epidemiologia , Herpesvirus Humano 8/imunologia , Adolescente , Adulto , Idoso , Argentina/epidemiologia , Brasil/epidemiologia , Chile/epidemiologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Infecções por Herpesviridae/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Soroepidemiológicos
17.
Rev Med Chil ; 132(11): 1403-6, 2004 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-15693204

RESUMO

We report a 78 year old male with prostatism, that was subjected to a prostate biopsy. The pathological study showed a microvascular lymphocytic infiltration. Four months later, the patients presented with reduced alertness, cough, dyspnea, fever and elevation of lactic dehydrogenase and erythrocyte sedimentation rate. Chest and abdominal CAT scans, bone marrow aspirate, protein electrophoresis and prostate specific antigen were normal. A re-evaluation of prostate biopsy showed an intravascular lymphoid infiltration, positive for CD45 and CD20, compatible with the diagnosis of intravascular lymphoma. Chemotherapy was started, but it was not tolerated by the patient and the response was partial. Therefore, treatment with monoclonal antibodies anti CD20 (Rituximab) was started. The tumor had a complete and prolonged (24 months) remission after the treatment


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Neoplasias Vasculares/tratamento farmacológico , Idoso , Anticorpos Monoclonais Murinos , Antígenos CD20/análise , Biópsia , Humanos , Masculino , Hiperplasia Prostática/patologia , Rituximab , Neoplasias Vasculares/patologia
18.
Rev. Hosp. Clin. Univ. Chile ; 15(2): 138-145, 2004. tab
Artigo em Espanhol | LILACS | ID: lil-476851

RESUMO

En este artículo se detallan el enfoque diagnóstico y terapéutico de las enfermedades hematológicas más frecuentes en el embarazo. Se describen las patologías que afectan a la línea eritrocitaria y plaquetaria, adicionándose también síndromes clínicos prevalentes como la PTT y el Síndrome HELLP. En la última parte, se analizan las manifestaciones clínicas de alteraciones de la hemostasia que causan hemorragias o trombosis, junto a su aproximación diagnóstica y manejo terapéutico.


Assuntos
Humanos , Feminino , Gravidez , Complicações Hematológicas na Gravidez , Anemia Hemolítica , Anemia Ferropriva , Anemia Megaloblástica , Síndrome Antifosfolipídica , Síndrome HELLP , Trombocitopenia , Doenças de von Willebrand
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